The answer is a i’m pretty sure, if i’m incorrect then i’m sorry but i’m sure that it’s a :)
What do you need help with?
Y=a(x-1)^2 -17 is the equation of the parabola.
at (0,16), 16=a(0-1)^2 -17. Solve for a = 33.
Equation is then y=33(x-1)^2-17 so when y=0,
(x-1)^2 = 17/33
x-1 = + and - square root of 17/33
x = 1.7177 and 0,2823 as the intercepts
